It will be hard to notice when President Trump does something worthy of hysteria if everything he does is greeted with hysteria. Take claims that he’s laying siege to the alleged chastity of climate scientists. This is one subject where it might be wise not to rely on the reflexive media narrative.

The year 2016 was the warmest ever recorded—so claimed two U.S. agencies, NASA’s Goddard Institute for Space Studies and the Commerce Department’s National Oceanic and Atmospheric Administration. Except it wasn’t, according to the agencies’ own measures of statistical uncertainty.

Such fudge is of fairly recent vintage. Leaving any discussion of the uncertainty interval out of press releases only became the norm in the second year of the Obama administration. Back when he was presenting the 2008 numbers, NASA’s James Hansen, no slouch in raising climate alarms, nevertheless made a point of being quoted saying such annual rankings can be “misleading because the difference in temperature between one year and another is often less than the uncertainty in the global average.”

Statisticians wouldn’t go through the trouble of assigning an uncertainty value unless it meant something. Two measurements separated by less than the margin of error are the same. And yet NASA’s Goddard Institute, now under Mr. Hansen’s successor Gavin Schmidt, put out a releasedeclaring 2014 the “warmest year in the modern record” when it was statistically indistinguishable from 2005 and 2010.

Nowadays Goddard seems to mention confidence interval only when it’s convenient. So 2015, an El Niño year, was the warmest yet “with 94 percent certainty.” No confidence interval was cited one year later in proclaiming 2016 the new warmest year “since modern recordkeeping began.” In fact, the difference versus 2015 was a mere one-quarter of the margin of error.

Commerce’s NOAA makes a fetish of ignoring confidence interval in its ranking of the 12 warmest years. Yet when statistical discipline is observed, 2015 and 2016, the two El Niño years, are tied for warmest. And the years 1998, 2003, 2005, 2006, 2007, 2009, 2010, 2012, 2013 and 2014 are all tied for second warmest.

In other words, whatever the cause of warming in the 1980s and 1990s, no certain trend is observable since then.

Shall we posit a theory about all this? U.S. government agencies stopped mentioning uncertainty ranges because they wanted to engender a steady succession of headlines pronouncing the latest year unambiguously the hottest when it wasn’t necessarily so.

This doesn’t mean you should stop being concerned about a potential human impact on climate. But when government scientists deliberately seek to mislead, it’s a warning to raise your guard.

For instance, NOAA states its annual temperature estimate as an “anomaly” in relation to the 20th-century average. Do you really believe government scientists can reconstruct a global average temperature for years in the first half of the 20th century with sufficient accuracy to allow comparisons of 1/100ths of a degree?

You start to notice other things. The numbers keep changing. Years 2005 and 2010 were exactly tied in 2010, but now 2010 is slightly warmer, just enough to impart an upward slope to any graph that ignores statistical uncertainty.

Government scientists are undoubtedly ready with justifications for each of the countless retroactive adjustments they impose on the data, but are you quite sure they can be trusted?

Climate science is not a hoax. The U.S. government spends impressive sums to take the increasingly rigorous readings from which a global average temperature is distilled. But other countries like the U.K. and Japan also do sophisticated monitoring and end up with findings roughly similar to the findings of U.S. agencies, yet they don’t feel the need to lie about it. For instance, the U.K. Met Office headlined its 2016 report “one of the warmest two years on record.” A reader only had to progress to the third paragraph to discover that the difference over 2015 was one-tenth the margin of error.

President Trump is a complete novice, but presumably at some point he will climb the learning curve, gain control over his administration, and start making cagier decisions about which fights are worth having. Our guess is that fighting with his administration’s climate scientists won’t seem like much of a priority. And yet, given all the money U.S. taxpayers spend on climate science, a mental freshening wouldn’t be the worst thing. Goddard’s Mr. Schmidt, keeper of a snarling blog that makes frequent use of the slur “denier,” got his start at the New York City-based NASA science lab more than 20 years ago.

On the slight chance Mr. Trump does make such a move, keep something else in mind: Undifferentiated hysteria will apparently be the media reaction to every Trump action equally whether those actions are entirely justified or entirely indefensible.